<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>边框</title>
    <style>
        .one {
            /*把4个边框 按照要素进行拆分,分别设置*/
            /*border: 1px dashed red;*/
            border-width: 10px 20px;
            border-style: dotted solid dashed;
            border-color: #FF0000 #00FF00 #00F #FF0;

        }

        .two {
            border-top: 5px solid #88F;
            border-bottom: 15px solid #11F;
            border-left: 25px solid #33F;
            border-right: 35px solid #99F;
        }

        .three {
            width: 0px;
            height: 0px;
            /*border: 50px solid red;*/
            border: 50px solid white;
            border-top: 50px solid green;
            border-bottom: none;
            /*border-right: none;*/
            /*border-left: none;*/
        }

        /*边框有三要素
        粗细, 线形, 颜色
        只有颜色可以不写,默认是黑色
        剩下的不写边框无法显示
        */
    </style>
</head>
<body>

<div class="one">
    老骥伏枥,
</div>

<div class="two">
    志在千里.
</div>

<div class="three">
123
</div>
</body>
</html>